Otostigmus striolatus Verhoeff, 1937

Lewis, John G. E., 2014, A review of the orientalis group of the Otostigmus subgenus Otostigmus Porat, 1876 (Chilopoda: Scolopendromorpha: Scolopendridae), Zootaxa 3889 (3), pp. 388-413 : 407

Otostigmus striolatus Verhoeff, 1937

( Figs 55–62 )

O. (Otostigmus) striolatus Verhoeff, 1937 , 214, Pl. 13, Figs 10, 12. Malacca [ Melaka] Malaysia O. striolatus: Verhoeff, 1942 , 185 (in key).

Diagnosis. Length 25–43 mm. Antennal articles 21 or 22, the basal 2.25–2.5 glabrous dorsally. Forcipular coxosternal teeth 6+6 to 6+8. Tergites with complete paramedian sutures from 8, marginate from 10, 11 or 12, with weak lateral corrugations and numerous very short fine ridges of variable length. Sternites without paramedian sutures, with numerous very short longitudinal grooves from 11–20. Coxopleural process with three or four apical and one lateral spine. Legs 1–18 with two tarsal spurs. Ultimate leg prefemora with 9–13 spines. No corner spine.

Material examined. ZMB. 1 specimen in ethanol, Malacca, Syntypus 2105, ZMB 13363.

ZSM. 2 slides each labelled Otostigmus striolatus Verh. Pahang 15–1600m. Malacca. A20030598 with forcipules and trunk segments 1–3, and 18–21 and two detached ultimate legs. A20030599 with head and mouth parts.

Description of ZMB specimen. (Verhoeff’s (1937) data in parentheses). Length approximately 25 (43) mm. Antennae with 22 (21–21) articles, the basal 2.25 (2½) glabrous. Forcipular coxosternal tooth-plates with 6+6 low teeth ( Fig. 55 ) not apparently due to wear (Verhoeff’s Abb. 7 shows 8+7). Forcipular trochanteroprefemoral process with two low denticles.

Tergites with complete paramedian sutures from 8, marginate from about 10 (11 or 12), weak lateral corrugations from 9, a low median keel from 12–19. With numerous very short fine ridges of variable length ( Fig. 56 ) (fine longitudinal scratched streaks/lines feinen geritzten Längsstricheln) from T3 covering complete tergite surface from 5 to 21 only seen when specimen dried off.

Sternites without paramedian sutures but with two shallow paramedian depressions from 9–19 and numerous short, narrow longitudinal grooves (scratches) from 11–20 ( Fig. 57 ). Sternite of ultimate leg-bearing segment with sides strongly convergent posteriorly and posterior margin concave ( Fig. 58 ). Coxopleural process very short, with three apical and one lateral spine, the pore field widening abruptly in its anterior half ( Fig. 58 ).

Legs 1–12 or 13 (1–4) with a tibial spur (two tarsal spurs on 1–18). Ultimate legs missing (prefemur with 9–13 spines, 4–6 ventral, 3 medial, 5 dorsomedial, no corner spine).

Description of ZSM specimen. Antennae with 22+19[d] articles, the basal 2.45 glabrous. Second maxillary pretarsus with accessory spines but lacking a spur on article 2. Forcipular coxosternal tooth-plates with 8+6 low teeth. The decision as to what does and does not count as a tooth is subjective. Trochanteroprefemoral process with two low medial denticles.

Sternite of ultimate leg-bearing segment trapezoidal, the posterior margin very slightly concave. Coxopleural process very short, with four apical spines, ( Fig. 59 ) or three apical and one lateral spine ( Fig. 60 ).

Ultimate leg prefemora with 8 (in rows of 4, 3 and 1) and 13 spines ( Figs 61, 62 ) the spine position uncertain in this cleared material.

Remarks. Otostigmus striolatus closely resembles O. multidens . However, Verhoeff (1937) stated that the fine longitudinal “as if scratched with a fine needle” streaks on the tergites and sternites differentiated this species from all others. Otostigmus multidens is widespread in South-East Asia and might well be expected to occur in Peninsular Malaysia but Verhoeff’s paper is the only publication on the centipede fauna of that region. Verhoeff’s description of O. striolatus is of the Munich specimen most of the trunk of which is missing.

Figures

FIGURES 55 – 62. Otostigmus striolatus. Syntypes. 55. Forcipular coxosternal tooth-plates ZMB spm. 56. Tergite 13 ZMB spm. (detail shown on left side only). 57. Sternite 16 ZMB spm. (partly freehand). 58. Ultimate leg-bearing segment ZMB spm. (detail of pores shown in posterior part of right coxopleuron). 59. Right coxopleural process ZSM spm. 60. Left coxopleural process ZSM spm. 61. Detached ultimate leg ZSM spm. 62. Second detached ultimate leg ZSM spm. FIGURES 63 – 67. Otostigmus sucki Syntypes. 63. Antennal article 3 dorsal spm. 2. 64. Right forcipular trochanteroprefemoral process and coxosternal tooth-plates spm. 3. 65. Ultimate tergite spm. 3. 66. Sternite of ultimate leg-bearing segment and left coxopleural process spm. 3. 67. Right prefemur ultimate leg spm 3 ventral. Scale bars = 1.0 mm except Figs 55, 58, 63 & 64 = 0.5 mm and Figs 59 & 60 = 0.1 mm.